Yes. Copyrights help you protect your intellectual property. You can place a copyright on your web page, and that may deter the common "intellectual property crook" from nabbing content from your site without permission. Or, you can place the copyright statement on your site and they'll take it anyway. What's your choices if they do? Eat it, or take them to court.

If you haven't registered your work at the US Copyright Office (http://lcweb.loc.gov/copyright/), you'll have an extremely difficult time (if not completely impossible) in defending your work because you cannot prove that you created the material first.